<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script type="text/javascript" src="http://mat1.gtimg.com/libs/jquery/1.12.0/jquery.js"></script>
</head>
<body>
<form action="" method="post">
{% csrf_token %}
帐号: <input type="text" name="uname" onblur="f()" id="n" value="{{ a }}"> <span id="s"></span><br>
密码: <input type="text" name="pwd" value="{{ b }}"><br>
<button>登录</button>
<input type="checkbox" value="1" name="e">记住密码
</form>
<script>
function f() {
var n = $('#n').val()
if (n.length === 0) {
$('#s').html('字段不能为空')
$('#s').css('color', 'red')
} else {
$('#s').html('对')
$('#s').css('color', 'blue')
}
}
</script>
</body>
</html>